Liquid cleaning composition



- and easy manner remains a Patented July 9, g

National Carbon Com of New York pany, Inc.,.a corporation No Drawing. Application April 22, 1943. Serial No. 484,067 I 2 Claims. (or. 252-118) a 1 The invention relates to the cleaning of metal surfaces, and is particularly concerned with' liquid cleaner compositions forremoving sludge deposits from the interior parts of internal com;- bustion engines.

Under ordinary operating conditions of an internal combustion engine there is usually formed in the crank case, on the surfaces of the combustion chamber, and on other interior. working parts, a precipitate or deposit commonly referred to as sludge. This sludge is formed in large partof decompositionprdducts of oil and fuel usedin the engine, and may be composed of heavy hydro- ,carbons, asphaltenes, gums, fine carbon, road dirt and other solid deposits. The sludge accumulates on, and becomes tightly bound to, the

piston .head and rings, the valve .stems and the bearings, and in sumciently large amounts it may markedly interfere with satisfactory engine operation. The removal of this sludge occasionally is, therefore, desirable, and while-eflorts have been made to accomplish this by means of various types and kinds of solvent cleaners, the matter of satisfactorily cleaning engines in :a quick dii'ncultand important problem.

It is an object of this invention to provide improved metal cleaner compositions, adapted more effectively, more readily, and more conven-' iently to remove sludge deposits from internal combustion engines.

The new cleaner is composed of a plurality ofcomponents, in controlled volume proportions to produce a, homogeneous liquid mixture of exceptionally rapidand effective cleaning action. As the essential loosening and dissoivingvagent for 2 of glycol monoalkyi ethersare good solvent components, and the cleansing action of these compounds can be further improved by mixingthem with an aliphatic ether compound. Especially effective among the latter solvents are the monoether derivatives of alkylene glycols. The most suitable proportions of each solvent in these mixtures can bereadily, determined by test, but the total solventquantity in the cleaner should preferably be from about 50% to 80% by volume.

Water in the cleaner formula substantially aids in loosening tightly bound sludge, and causes flaking off of lacquer-type deposits, which might not otherwise be attacked by the solvent. At 1 least 4 water is necessary to improve the cleaner performance, and it preferably should not exceed by volume. The purpose of an oil addition is to afl'ordlubricating properties, and prevent rusting of the metal surfaces after cleaning; Ordinary mineral lubricating oils are satisfactory for this use, and the oil proportions preferably vary from about 15% to 25% by volume. A coupling agent is necessary to render the oil-water-solvent mixture homogeneous, and, thereby insure proper functioning of the cleaner.

A both as initially formulated'and after storage in the sludge deposits, one or more organic solvents are used in an amount comprising at least 50% by volume of the total mixture. Water in an amount from about 4% to 25% of the whole, and

oil in quantities preferably not exceeding about by volume are mixed with the solvent, and a coupling agent is then added to produce a stable and homogeneous liquid composition. A detergent mayalso be included, but by preference the coupling agent selected is one which also will exert a detergent action.

Suitable solvents for this cleaner may be selected from organic ethers and esters, and the best results have been obtained with mixtures of two or more solvents. The heterogeneous nature of the sludge deposit appears to account for the fact that a singlesolvent does not usually dissolve or loosen the deposit as well as a mixture w of two or more of them. Carboxylic acid esters containers. Some .of the solvents above mentioned may in themselves assist in coupling of the completed mixture, but a further additive speciflcallyfor this purpose is usually desirable. Many compounds are available which may be suitable in their homogenizing eifect, among which amine soaps are preferred, since thesecompounds also have certain detergent action,

andthus further improve the solvent emciency. Morpholine soaps, such as morpholine oleate and morpholine ricinoleate have prove especially effective as coupling and detergency agents. A fatty acid, such as oleic acid, may also be added in addition to the amine soap, if desired, and

may aid in softening'the lacquer-like hard deposits on valve stems, piston heads and rings. The amine soap proportions are generally be- :tween about 5% and 20% by volume, and the fatty acid, if used, preferably should not exceed about 10%.

A complete cleanerformula representative of the invention; which has proven particularly effective in the cleaning of automobile engines, is

shown the followng table:

, Per cent by vo umo Mineral lubricating oil 8. A. E. 20 18 Water 4 Ethylene glycol utyl ether l8 Ethylene glycol yl ether 32 Morpholine oleste. 10 Oleic acida aeoaeio cleaner compositions, no restrictions are intended by the present disclosure, but a distinct advantage lies in the ease and convenience with which satisfactory cleaning can be effected. With an engine still in running order, a clea'ning treatment may consist in slowly adding a pint or so of the sludge remover through the carburetor air intake while operating at a speed just sufiicient to prevent stalling. In this process the cleaner is carried directly into the combustion chambers and is later expelled through the exhaust manifold. Thus, the valves, pistons, piston rings and combustion chambers are exposed to the cleaner, and the very small quantities of the cleaner which may pass the piston rings into the crank case, are not sufiicient to cause any deleterious action on, or dilution of, the crank case oil. l

Where the sludging is very severe and the most eflective cleaning action is desired, the treatment above can be augmented by crank case cleaning. This is accomplished by draining the crank case and refilling it to normal level with the concentrated cleaner formula before starting addition of cleaner to the carburetor. At the conclusion of the carburetor treatment, the crank case is again drained, and may be flushed with light oil. This combination treatment effects excellent cleaning of the-crank case, inner engine surfaces, bearings and oil passages, as well as all parts of the combustion chambers. In case oi complete engine seizure by heavy sludge, introduction of the cleaner into the spark plug holes, followed by a period of soaking, is usually effective in loosening the deposits. Where overhauling or dismantling of the engine is necessary, the cleaner composition can, of course, be used in the ordinary way, and will be found r-apidly effective in cleaningall metal surfaces.

'In the particular; liquid mixtures proposed, consideration has also been given to factors such as toxicity and odor-,fiash point, corrosiveness, and attack on gasket-materials. These formulae are satisfactory in such respects, having no odor'that is obnoxious, and being entirely safe to handle under the ordinary precautions used in handling common solvents. They are not irritating to the skin,- and they do not readily corrode metals or attack gasket material.

It will be understood, however, thatthe specific cleaner formula given is merely representative, and that numerous modifications in the various components, and their proportions, may be made with the advantages described. Such modifications are intended to be included within the broader scope of the invention. This application is a continuation-in-part of my copending application Serial No. 438,077, filed April 8, 1942.

I claim: v 1. A cleaning composition for removing sludge from internal combustion engines consisting of a homogeneous liquid mixture of a solvent composed of ethylene glycol monoethyl ether acetate and ethylene glycol .monobutyl ether, in appreciable component proportions and in a total amount of about to by volume; a lubricating oil in an amount from about 15% to 25%; about 4% to 25% of water; about 5% to 20% of morpholine oleate; and not more than about 10% oleic acid.

2, A cleaning composition for removing sludge from internal combustion engines comprising a homogeneous liquid mixture, in proportion by volume of about 32% ethylene glycol monoethyl ether acetate, about 18% ethylene glycol monobutyl .ether, about 18% mineral lubricating oil, about 4% water, about 19% morpholine oleate, and about 9% oleic acid.

GEORGE M. SKINNER. 

